import type { PendingToolInterrupt } from '#src/core/types.js';
/**
 * The opening sentence of the approval prompt for one gated call, **without** any surface's own
 * punctuation or styling.
 *
 * Three arms, one per subject kind:
 *
 * - `shell` — *The agent wants to run a shell command via `<tool>`*, unchanged, so the case that was
 *   already clear stays clear.
 * - `mcpTool` — *The agent wants to call `<name>` on the MCP server `<server>`, via `<tool>`*.
 *   **Naming the server is a deliberate addition rather than a side effect**: the subject already
 *   carries it, and which server a call reaches is the one load-bearing fact the old prompt hid.
 * - `tool` — *The agent wants to use the `<tool>` tool*.
 *
 * **An MCP call whose server would print as a blank falls to the `tool` arm.** The `mcpTool`
 * sentence would otherwise read "on the MCP server , via …" — nothing where the decisive word goes.
 * The `tool` arm names the full registered name instead, which still carries the visible `mcp__`
 * namespace, and invents no prose claiming a server nothing could attribute.
 *
 * **A pending call with no subject also falls to the `tool` arm**, which is true of any gated call
 * and false of none. The runner attaches a subject to every interrupt it hands the approval
 * callback (asserted in `packages/core/spec/approvalPromptHeader.spec.ts`), so this is a floor
 * rather than a path: a surface handed a hand-built interrupt gets the vague sentence, never a
 * wrong one.
 *
 * @param pending The gated call — its registered name, and the subject the gate decided on.
 */
export declare function approvalPromptHeader(pending: Pick<PendingToolInterrupt, 'name' | 'subject'>): string;